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Figueroa-Ochoa EB, Bravo-Anaya LM, Vaca-López R, Landázuri-Gómez G, Rosales-Rivera LC, Diaz-Vidal T, Carvajal F, Macías-Balleza ER, Rharbi Y, Soltero-Martínez JFA. Structural Behavior of Amphiphilic Triblock Copolymer P104/Water System. Polymers (Basel) 2023; 15:polym15112551. [PMID: 37299350 DOI: 10.3390/polym15112551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Revised: 05/26/2023] [Accepted: 05/28/2023] [Indexed: 06/12/2023] Open
Abstract
A detailed study of the different structural transitions of the triblock copolymer PEO27-PPO61-PEO27 (P104) in water, in the dilute and semi-dilute regions, is addressed here as a function of temperature and P104 concentration (CP104) by mean of complimentary methods: viscosimetry, densimetry, dynamic light scattering, turbidimetry, polarized microscopy, and rheometry. The hydration profile was calculated through density and sound velocity measurements. It was possible to identify the regions where monomers exist, spherical micelle formation, elongated cylindrical micelles formation, clouding points, and liquid crystalline behavior. We report a partial phase diagram including information for P104 concentrations from 1 × 10-4 to 90 wt.% and temperatures from 20 to 75 °C that will be helpful for further interaction studies with hydrophobic molecules or active principles for drug delivery.
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Affiliation(s)
- Edgar Benjamín Figueroa-Ochoa
- Departamento de Química, Universidad de Guadalajara, Blvd. M. García Barragán #1451, Guadalajara 44430, Jalisco, Mexico
| | - Lourdes Mónica Bravo-Anaya
- Université Grenoble Alpes, CNRS, Grenoble INP (Institut of Engineering Univ. Grenoble Alpes), 38000 Grenoble, France
- Departamento de Ingeniería Química, Universidad de Guadalajara, Blvd. M. García Barragán #1451, Guadalajara 44430, Jalisco, Mexico
- Université de Rennes, Institut des Sciences Chimiques de Rennes, Équipe CORINT, CNRS, UMR 6226, Campus de Beaulieu, Bat 10A, 35042 Rennes Cedex, France
| | - Ricardo Vaca-López
- Departamento de Química, Universidad de Guadalajara, Blvd. M. García Barragán #1451, Guadalajara 44430, Jalisco, Mexico
| | - Gabriel Landázuri-Gómez
- Université Grenoble Alpes, CNRS, Grenoble INP (Institut of Engineering Univ. Grenoble Alpes), 38000 Grenoble, France
- Departamento de Ingeniería Química, Universidad de Guadalajara, Blvd. M. García Barragán #1451, Guadalajara 44430, Jalisco, Mexico
| | - Luis Carlos Rosales-Rivera
- Departamento de Ingeniería Química, Universidad de Guadalajara, Blvd. M. García Barragán #1451, Guadalajara 44430, Jalisco, Mexico
| | - Tania Diaz-Vidal
- Departamento de Ingeniería Química, Universidad de Guadalajara, Blvd. M. García Barragán #1451, Guadalajara 44430, Jalisco, Mexico
| | - Francisco Carvajal
- Centro Universitario UTEG, Departamento de Investigación, Héroes Ferrocarrileros #1325, Guadalajara 44460, Jalisco, Mexico
- CUTonalá, Departamento de Ingenierías, Universidad de Guadalajara, Nuevo Periférico # 555, Ejido San José Tatepozco 45425, Jalisco, Mexico
| | - Emma Rebeca Macías-Balleza
- Departamento de Ingeniería Química, Universidad de Guadalajara, Blvd. M. García Barragán #1451, Guadalajara 44430, Jalisco, Mexico
| | - Yahya Rharbi
- Université Grenoble Alpes, CNRS, Grenoble INP (Institut of Engineering Univ. Grenoble Alpes), 38000 Grenoble, France
| | - J Félix Armando Soltero-Martínez
- Université Grenoble Alpes, CNRS, Grenoble INP (Institut of Engineering Univ. Grenoble Alpes), 38000 Grenoble, France
- Departamento de Ingeniería Química, Universidad de Guadalajara, Blvd. M. García Barragán #1451, Guadalajara 44430, Jalisco, Mexico
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2
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McCauley PJ, Kumar S, Calabrese MA. Criteria Governing Rod Formation and Growth in Nonionic Polymer Micelles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:11676-11687. [PMID: 34601878 DOI: 10.1021/acs.langmuir.1c01570] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Self-assembled wormlike micelles (WLMs) are widely studied in small-molecule surfactants due to their unique ability to break and recombine; however, less is known about the structure and dynamics of nonionic polymer WLMs. Here, solutions of seven triblock poloxamers, composed of poly(propylene oxide) (PPO) midblocks and poly(ethylene oxide) (PEO) end blocks, are comprehensively examined to determine the role of poloxamer composition, temperature, and inorganic salt type and concentration on rod formation and subsequent elongation into WLMs. Phase separation and sphere-to-rod transition temperatures were quantified via cloud point measurements and shear rheology, respectively, and corroborated with small-angle neutron scattering (SANS). The local microstructure of resulting rodlike micelles is remarkably similar across poloxamer type and sodium fluoride (NaF) or sodium chloride (NaCl) content. Salt addition reduces transition temperatures, with the most pronounced effects for poloxamers with high PEO molecular weights and PEO fractions. Between these two temperatures, several poloxamers elongate into WLMs, where shear rheology detects increases in viscosity up to 6 orders of magnitude. Despite similar local microstructures, poloxamer identity and salt content impact micelle growth substantially, where large poloxamers with lower PEO fractions exhibit the highest viscosities and longest relaxation times. While sodium fluoride has little impact on micelle growth, increasing NaCl concentration dramatically increases the WLM viscosity and relaxation time. This result is explained by different interactions of each salt with the micelle: whereas NaF interacts primarily with PEO chains, NaCl may also partition to the PPO/PEO interface in low levels, increasing micelle surface tension, scission energy, and contour length.
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Affiliation(s)
- Patrick J McCauley
- Department of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Avenue SE, Minneapolis, Minnesota 55455-0132, United States
| | - Satish Kumar
- Department of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Avenue SE, Minneapolis, Minnesota 55455-0132, United States
| | - Michelle A Calabrese
- Department of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Avenue SE, Minneapolis, Minnesota 55455-0132, United States
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Fraenza CC, Mattea C, Farrher GD, Ordikhani-Seyedlar A, Stapf S, Anoardo E. Rouse dynamics in PEO-PPO-PEO block-copolymers in aqueous solution as observed through fast field-cycling NMR relaxometry. POLYMER 2018. [DOI: 10.1016/j.polymer.2018.07.027] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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4
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García Daza FA, Bonet Avalos J, Mackie AD. Logarithmic Exchange Kinetics in Monodisperse Copolymeric Micelles. PHYSICAL REVIEW LETTERS 2017; 118:248001. [PMID: 28665650 DOI: 10.1103/physrevlett.118.248001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Indexed: 06/07/2023]
Abstract
Experimental measurements of the relaxation kinetics of copolymeric surfactant exchange for micellar systems unexpectedly show a peculiar logarithmic decay. Several authors use polydispersity as an explanation for this behavior. However, in coarse-grained simulations that preserve microscopic details of the surfactants, we find evidence of the same logarithmic behavior. Since we use a strictly monodisperse distribution of chain lengths such a relaxation process cannot be attributed to polydispersity, but has to be caused by an inherent physical process characteristic of this type of system. This is supported by the fact that the decay is specifically logarithmic and not a power law with an exponent inherited from the particular polydispersity distribution of the sample. We suggest that the degeneracy of the energy states of the hydrophobic block in the core, which is broken on leaving the micelle, can qualitatively explain the broad distribution of energy barriers, which gives rise to the observed nonexponential relaxation.
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Affiliation(s)
- Fabián A García Daza
- Departament d'Enginyeria Química, ETSEQ, Universitat Rovira i Virgili, Avinguda dels Països Catalans 26, 43007 Tarragona, Spain
| | - Josep Bonet Avalos
- Departament d'Enginyeria Química, ETSEQ, Universitat Rovira i Virgili, Avinguda dels Països Catalans 26, 43007 Tarragona, Spain
| | - Allan D Mackie
- Departament d'Enginyeria Química, ETSEQ, Universitat Rovira i Virgili, Avinguda dels Països Catalans 26, 43007 Tarragona, Spain
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Arranja A, Waton G, Schosseler F, Mendes E. Lack of a unique kinetic pathway in the growth and decay of Pluronic micelles. SOFT MATTER 2016; 12:769-778. [PMID: 26523415 DOI: 10.1039/c5sm02353j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We report kinetic experiments on dilute brine solutions of P84, P94 and P104 Pluronic copolymer micelles. The growth and the decay of micelles after temperature steps are measured by non-standard time resolved multi-angle photon correlation spectroscopy. Several concurrent mechanisms are at work during the very slow equilibration of solutions, namely insertion/expulsion of unimers, aggregation/dissociation of micellar aggregates, and fusion/budding of micellar aggregates. Their relative rates determine both the kinetic pathways and the morphologies of the micellar assemblies, which depend markedly on modest changes in the copolymer molecular weight. For the typical Pluronic copolymers investigated here, none of these elementary processes can be neglected if the resulting morphology is to be explained. This feature imposes multiple kinetic behaviours where growth and decay of Pluronic micelles become strongly dependent on the thermal history. We point out to some possible shortcomings in the studies of micellar growth kinetics by light scattering techniques. Extensive time-resolved multiangle measurements are a prerequisite for avoiding these pitfalls.
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Affiliation(s)
- Alexandra Arranja
- Institut Charles Sadron, University of Strasbourg, CNRS UPR 22, 23 rue du Loess, 67034 Strasbourg Cedex 2, France.
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Structural modifications in polymeric micelles to impart multifunctionality for improved drug delivery. Ther Deliv 2016; 7:73-87. [PMID: 26769002 DOI: 10.4155/tde.15.90] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Polymeric micelles are macromolecular nanoconstructs which are formed by self-assembly of synthetic amphiphilic block copolymers. These copolymers could be chemically modified to expand their functionality and hence obtain a multifunctional micelle which could serve several functions simultaneously, for example, long circulation time along with active targeting, smart polymeric micelles providing on-demand drug release for example, pH responsive micelles, redox- and light-sensitive micelles, charge-conversion micelles and core/shell cross-linked micelles. Additionally, micelles could be tailored to carry a contrast agent or siRNA/miRNA along with the drug for greater clinical benefit. The focus of the current commentary would be to highlight such chemical modifications which impart multifunctionality to a single carrier and discuss challenges involved in clinical translation of these multifunctional micelles.
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8
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Khimani M, Parekh P, Aswal VK, Bahadur P. Interaction, solubilization and location of p-hydroxybenzoic acid and its sodium salt in micelles of moderately hydrophilic PEO-PPO-PEO triblock copolymers. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2014; 37:38. [PMID: 24853632 DOI: 10.1140/epje/i2014-14038-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 04/15/2014] [Accepted: 04/25/2014] [Indexed: 06/03/2023]
Abstract
Micelles of ABA type triblock copolymers (where A is polyethylene oxide PEO and B is polypropylene oxide PPO) viz. Pluronic® P103, P104 and P105 (each containing almost the same PPO mol wt. ~ 3250 g/mol and 30, 40 and 50 wt.% of PEO, respectively) in the presence of p -hydroxybenzoic acid (PHBA) and its sodium salt (Na-PHBA) were examined by viscosity, dynamic light scattering (DLS), small angle neutron scattering (SANS) and NMR. Spherical polymeric micelles (apparent hydrodynamic diameter ~ 20 nm) in water at 30 °C grow in the presence of PHBA and transform into prolate-ellipsoidal shape with an increased aggregation number. The micellar transition was favored at higher PHBA concentration, temperature and for copolymers with more hydrophobicity. The PHBA salt, however, increased cloud point and showed only a marginal decrease in aggregation number even at much higher concentrations. The location of PHBA in micelle was elucidated by nuclear Overhauser enhancement spectroscopy (NOESY).
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Affiliation(s)
- Mehul Khimani
- Department of Chemistry, Veer Narmad South Gujarat University, 395 007, Surat, India,
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9
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Torcello-Gómez A, Wulff-Pérez M, Gálvez-Ruiz MJ, Martín-Rodríguez A, Cabrerizo-Vílchez M, Maldonado-Valderrama J. Block copolymers at interfaces: interactions with physiological media. Adv Colloid Interface Sci 2014; 206:414-27. [PMID: 24268588 DOI: 10.1016/j.cis.2013.10.027] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2013] [Revised: 10/23/2013] [Accepted: 10/23/2013] [Indexed: 12/20/2022]
Abstract
Triblock copolymers (also known as Pluronics or poloxamers) are biocompatible molecules composed of hydrophobic and hydrophilic blocks with different lengths. They have received much attention recently owing to their applicability for targeted delivery of hydrophobic compounds. Their unique molecular structure facilitates the formation of dynamic aggregates which are able to transport lipid soluble compounds. However, these structures can be unstable and tend to solubilize within the blood stream. The use of nanoemulsions as carriers for the lipid soluble compounds appears as a new alternative with improved protection against physiological media. The interfacial behavior of block copolymers is directly related to their peculiar molecular structure and further knowledge could provide a rational use in the design of poloxamer-stabilized nanoemulsions. This review aims to combine the new insights gained recently into the interfacial properties of block copolymers and their performance in nanoemulsions. Direct studies dealing with the interactions with physiological media are also reviewed in order to address issues relating metabolism degradation profiles. A better understanding of the physico-chemical and interfacial properties of block copolymers will allow their manipulation to modulate lipolysis, hence allowing the rational design of nanocarriers with efficient controlled release.
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10
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Fuller JM, Raghupathi KR, Ramireddy RR, Subrahmanyam AV, Yesilyurt V, Thayumanavan S. Temperature-sensitive transitions below LCST in amphiphilic dendritic assemblies: host-guest implications. J Am Chem Soc 2013; 135:8947-54. [PMID: 23692369 PMCID: PMC3706455 DOI: 10.1021/ja402019c] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Oligo(ethylene glycol)-decorated supramolecular assemblies have been of great interest due to their charge-neutral character and thus their propensity to avoid nonspecific interactions. These systems are known to exhibit a macroscopic temperature-sensitive transition, where the assembly phase-separates from the aqueous phase at higher temperatures. While this so-called lower critical solution temperature (LCST) behavior has been well-studied, there have been no studies on the fate of these supramolecular assemblies below this transition temperature. The work here brings to light the presence of a second, sub-LCST transition, observed well below the LCST of oligo(ethylene glycol) (OEG)-based dendrons, where the host-guest properties of the assembly are significantly altered. This sub-LCST transition is accompanied by changes in the guest encapsulation stability and dynamics of host exchange.
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Affiliation(s)
| | | | | | | | - Volkan Yesilyurt
- Department of Chemistry, University of Massachusetts, Amherst, MA 01003
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11
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Lund R, Willner L, Richter D. Kinetics of Block Copolymer Micelles Studied by Small-Angle Scattering Methods. CONTROLLED POLYMERIZATION AND POLYMERIC STRUCTURES 2013. [DOI: 10.1007/12_2012_204] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
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12
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Khimani M, Ganguly R, Aswal VK, Nath S, Bahadur P. Solubilization of parabens in aqueous Pluronic solutions: investigating the micellar growth and interaction as a function of paraben composition. J Phys Chem B 2012; 116:14943-50. [PMID: 23210422 DOI: 10.1021/jp308738s] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The influence of methyl paraben (MP) and butyl paraben (BP) on the aggregation characteristics of Pluronics in an aqueous medium has been investigated by DLS, SANS, viscometry, and fluorescence measurement techniques. Parabens are extensively used as preservatives in cosmetic, pharmaceutical, and food products. In this paper, we show that their influence on the restructuring and growth of Pluronics micelles vary quite significantly with their aqueous solubility and with the composition of Pluronics. In the case of P105 and P104, MP reduces the sphere-to-rod transition temperature down to room temperature, but BP with significantly less aqueous solubility than MP suppresses such micellar transition and leads to the formation of micellar clusters due to the onset of intermicellar attractive interaction. In the case of more hydrophobic Pluronic P103, on the other hand, both MP and BP are able to induce rapid room temperature sphere-to-rod micellar growth, which is not observed in the presence of water structure making salts like NaCl and Na(3)PO(4). These observations have been attributed to modulation of growth and restructuring processes of the Pluronic micelles arising due to different locations of parabens within the micellar corona as determined by their aqueous solubility and the hydrophobicity of the Pluronics.
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Affiliation(s)
- M Khimani
- Department of Chemistry, Veer Narmad South Gujarat University, Surat-395007, India
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Landazuri G, Fernandez VVA, Soltero JFA, Rharbi Y. Kinetics of the sphere-to-rod like micelle transition in a pluronic triblock copolymer. J Phys Chem B 2012; 116:11720-7. [PMID: 22934621 DOI: 10.1021/jp3009089] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The kinetics of the sphere-to-rod transition was studied in aqueous micelle solutions of triblock copolymer poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) pluronic P103 (PEO(17)PPO(60)PEO(17)). This transition was triggered by a temperature jump from the sphere phase to the rod phase and monitored with dynamic light scattering. The combination of the scattering intensity and the hydrodynamic radius were used to show that the micelles grow steadily as rods throughout the growth process. The transition was found to exhibit a single exponential behavior even in the case of large deviations from equilibrium. The linear increase in the decay rate with increasing copolymer concentration shows that the transition is dominated by a mechanism involving fusion and fragmentation of proper micelles. The decays of the sphere-to-rod transition were simulated for two pathways: random fusion fragmentation and successive addition of spherical micelles to rods. We show that micelle growth most likely occurs via random fusion-fragmentation. The second order rate constant for fusion and the fragmentation rate are calculated for the case of random fusion-fragmentation.
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Affiliation(s)
- Gabriel Landazuri
- Laboratoire de Rhéologie, UJF/INPG/CNRS, UMR 5520, B.P.53, F-38041 Grenoble Cedex 9, France
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14
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Lund R. Small Angle Neutron Scattering as a Tool to Study Kinetics of Block Copolymer Micelles. ACTA ACUST UNITED AC 2009. [DOI: 10.1007/978-3-642-03309-4_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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15
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Fernandez VVA, Soltero JFA, Puig JE, Rharbi Y. Temporal Evolution of the Size Distribution during Exchange Kinetics of Pluronic P103 at Low Temperatures. J Phys Chem B 2009; 113:3015-23. [DOI: 10.1021/jp809685q] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- V. V. A. Fernandez
- Laboratoire de Rhéologie, UJF/INPG/CNRS, UMR 5520, B.P.53, F-38041 Grenoble Cedex 9, France, and Departamentos de Ingeniería Química, Universidad de Guadalajara, Boul. M. García Barragán # 1451, Guadalajara, Jal. 44430, México
| | - J. F. A. Soltero
- Laboratoire de Rhéologie, UJF/INPG/CNRS, UMR 5520, B.P.53, F-38041 Grenoble Cedex 9, France, and Departamentos de Ingeniería Química, Universidad de Guadalajara, Boul. M. García Barragán # 1451, Guadalajara, Jal. 44430, México
| | - J. E. Puig
- Laboratoire de Rhéologie, UJF/INPG/CNRS, UMR 5520, B.P.53, F-38041 Grenoble Cedex 9, France, and Departamentos de Ingeniería Química, Universidad de Guadalajara, Boul. M. García Barragán # 1451, Guadalajara, Jal. 44430, México
| | - Y. Rharbi
- Laboratoire de Rhéologie, UJF/INPG/CNRS, UMR 5520, B.P.53, F-38041 Grenoble Cedex 9, France, and Departamentos de Ingeniería Química, Universidad de Guadalajara, Boul. M. García Barragán # 1451, Guadalajara, Jal. 44430, México
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Ye X, Lu Y, Liu S, Zhang G, Wu C. Ultrafast infrared heating laser pulse-induced micellization kinetics of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) in water. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:10366-71. [PMID: 17705518 DOI: 10.1021/la701626k] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The heating-induced micellization of poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) (Pluronic PE10300) triblock copolymer chains was studied by ultrasensitive differential scanning calorimetry, laser light scattering, and fluorescence spectrometry with a fluorescent probe, 8-anilino-1-naphthalenesulfonic acid ammonium salt. The critical micellization temperatures obtained from the three methods are similar. The micellization kinetics was studied in terms of changes in the fluorescence and Rayleigh scattering intensities after an ultrafast infrared heating laser pulse (approximately 10 ns)-induced temperature jump. The increases in the fluorescence and Rayleigh scattering intensities in the millisecond range can be well described by a single-exponential equation, corresponding to the incorporation of individual triblock copolymer chains (unimers) into large spherical micelles. The increase in copolymer concentration or the initial solution temperature decreases the characteristic transition time. In general, the fluorescence measurement has a better signal-to-noise ratio but leads to a transition time that is slightly shorter than that from the corresponding Rayleigh scattering measurement for a given copolymer solution.
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Affiliation(s)
- Xiaodong Ye
- The Hefei National Laboratory for Physical Sciences at Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
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Nakashima K, Bahadur P. Aggregation of water-soluble block copolymers in aqueous solutions: recent trends. Adv Colloid Interface Sci 2006; 123-126:75-96. [PMID: 16860770 DOI: 10.1016/j.cis.2006.05.016] [Citation(s) in RCA: 197] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
This review summarizes recent literature and some of our own results on aggregation behavior on water-soluble block copolymers belonging to three different classes viz. hydrophilic-hydrophobic (AB, ABA and BAB) block copolymers, double hydrophilic block copolymers (DHBCs) and ABC triblock copolymers. In the case of amphiphilic copolymers, special attention has been focussed on aggregation of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) triblock copolymers (Pluronics) and their aggregation in aqueous solutions at different temperatures as well as in the presence of various additives. Recent studies based on modern techniques viz. scattering (static and dynamic light scattering and small angle neutron scattering), spectral methods, e.g., fluorescence (static and time resolved), nuclear magnetic resonance and Fourier transform infrared spectroscopies, thermal methods e.g., differential scanning calorimetry and isothermal titration calorimetry, cryotransmission electron microscopy, ultrasonic absorption along with general physical properties like surface tension, viscosity and dye solubilization are summarized. For the DHBCs where one of the blocks is usually a polyion, complex formation by adding oppositely charged ions induces the formation of nanoaggregates. Characterization of such nanoaggregates of polyion complexes of DHBCs and their potential use for incorporation of ionic solutes in the micellar core are reviewed. The formation and characteristics of core-shell-corona micelles of ABC triblock copolymers and their applications as vehicles for controlled drug release are also discussed.
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Affiliation(s)
- Kenichi Nakashima
- Department of Chemistry, Faculty of Science and Engineering, Saga University, 1 Honjo-machi, Saga 840-8502, Japan
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18
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Zana R, Marques C, Johner A. Dynamics of micelles of the triblock copolymers poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) in aqueous solution. Adv Colloid Interface Sci 2006; 123-126:345-51. [PMID: 16854361 DOI: 10.1016/j.cis.2006.05.011] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
A number of results reported on the kinetics of exchange of triblock copolymers poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide), PEO-PPO-PEO, between micelles and the intermicellar aqueous solution are reviewed and analyzed to extract the rate constants k(+) for the entry of a copolymer into a micelle and k(-) for the exit of a copolymer from a micelle. Contrary to what is generally observed for conventional surfactants, the rate constant for the entry of a copolymer into a micelle is slower to much slower than for a diffusion-controlled process and decreases as the degree of polymerization of the PO block, n(PO), increases. The effect of the degree of polymerization of the EO block, n(EO), on the two rate constants is significant only for low values of n(EO). The variation of k(-) with n(PO) strongly suggests that the free copolymer molecule adopts a conformation where the PO block is tightly coiled with little contact with water and not a fully extended and hydrated conformation, in contrast to what is commonly assumed when analyzing the dependence of the cmc on the polymerization degree of the hydrophobic block.
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Affiliation(s)
- Raoul Zana
- Institut C. Sadron, CNRS, 6 rue Boussingault, 67000 Strasbourg, France.
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Zhu Z, Armes SP, Liu S. pH-Induced Micellization Kinetics of ABC Triblock Copolymers Measured by Stopped-Flow Light Scattering. Macromolecules 2005. [DOI: 10.1021/ma051808c] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Zhiyuan Zhu
- Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, 230026, Anhui Province, P. R. China; Department of Chemistry, University of Sheffield, Brook Hill, Sheffield, South Yorkshire, S37HF United Kingdom; and The Hefei National Laboratory for Physical Sciences at Microscale, Hefei, Anhui, P. R. China
| | - Steven P. Armes
- Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, 230026, Anhui Province, P. R. China; Department of Chemistry, University of Sheffield, Brook Hill, Sheffield, South Yorkshire, S37HF United Kingdom; and The Hefei National Laboratory for Physical Sciences at Microscale, Hefei, Anhui, P. R. China
| | - Shiyong Liu
- Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, 230026, Anhui Province, P. R. China; Department of Chemistry, University of Sheffield, Brook Hill, Sheffield, South Yorkshire, S37HF United Kingdom; and The Hefei National Laboratory for Physical Sciences at Microscale, Hefei, Anhui, P. R. China
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20
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Istratov V, Kautz H, Kim YK, Schubert R, Frey H. Linear-dendritic nonionic poly(propylene oxide)–polyglycerol surfactants. Tetrahedron 2003. [DOI: 10.1016/s0040-4020(03)00470-8] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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21
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d'Acunz F, Kohn J. Alternating Multiblock Amphiphilic Copolymers of PEG and Tyrosine-Derived Diphenols. 1. Synthesis and Characterization. Macromolecules 2002. [DOI: 10.1021/ma0113879] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Francesca d'Acunz
- Department of Chemistry, Rutgers-The State University of New Jersey, Piscataway, New Jersey 08854
| | - Joachim Kohn
- Department of Chemistry, Rutgers-The State University of New Jersey, Piscataway, New Jersey 08854
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22
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Abstract
Previous studies on surfactant adsorption mostly deal with dilute systems without aggregation in the bulk phase. At the same time, micellar solutions can be more important from the point of view of applications. If one attempts to estimate the equilibrium adsorption, neglecting the influence of micelles can lead to reasonable results. The situation differs for non-equilibrium systems when the adsorption rate can increase by an order of magnitude at the increase of the surfactant concentration beyond the CMC. A critical survey of various models describing the influence of micelles on adsorption kinetics at the liquid-gas interface is given and the theoretical results are compared with existing experimental data. The theories proposed for the case of large deviations from the equilibrium are usually based on some unjustifiable assumptions and can describe the kinetic dependencies of adsorption in only a limited number of situations. Consequently, only rough estimates of the kinetic coefficients of micellization can be obtained from experimental data on dynamic surface tension. More rigorous equations can be derived if the system only deviates slightly from equilibrium. In the latter case, the agreement between theoretical and experimental results is essentially better and measurements of the dynamic surface elasticity of micellar solutions allow us to study the micellization kinetics.
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Affiliation(s)
- B A Noskov
- Research Institute of Chemistry, St. Petersburg State University, Russia.
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23
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Evidence of micelle growth in aqueous solutions of the amphiphilic poly(ethylene oxide)–poly(propylene oxide)–poly(ethylene oxide) triblock copolymers from differential scanning microcalorimetry. Colloids Surf A Physicochem Eng Asp 2001. [DOI: 10.1016/s0927-7757(01)00539-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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24
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Waton G, Michels B, Zana R. Dynamics of Block Copolymer Micelles in Aqueous Solution. Macromolecules 2001. [DOI: 10.1021/ma001170z] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Gilles Waton
- Laboratoire de Dynamique des Fluides Complexes (CNRS-ULP), 4 rue B. Pascal, 67000 Strasbourg, France, and Institut Charles Sadron (CNRS-ULP), 6 rue Boussingault, 67000 Strasbourg, France
| | - Bernard Michels
- Laboratoire de Dynamique des Fluides Complexes (CNRS-ULP), 4 rue B. Pascal, 67000 Strasbourg, France, and Institut Charles Sadron (CNRS-ULP), 6 rue Boussingault, 67000 Strasbourg, France
| | - Raoul Zana
- Laboratoire de Dynamique des Fluides Complexes (CNRS-ULP), 4 rue B. Pascal, 67000 Strasbourg, France, and Institut Charles Sadron (CNRS-ULP), 6 rue Boussingault, 67000 Strasbourg, France
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